Process of agglomerating materials.



U IT D PATENT 'oF I re WILHELM SGHUMACHER, or osNABRUoK, GERMANY, ASSIGNOltTO ERNs/r TniiLMANn, p NEW YORK, NY.

PROCESS OF AGGLOMER ATING MATERIALS,

Specification of Letters Patent.

Patented July 9, 1907.

Application. filed December 26, 1906. Serial No. $4 9,486-

To .all whom it may concern:

Be it known that I, WILHELM ScHuMAcHER, a subject of the Emperor of Germany, and a residentoiOsnabriick, Germany, have invented certain new arid useful Improvements in Processes for Agglomerating Materials, of which the following is a specification.

My invention relates to the preparation of a very effective binder for agglomerating comminuted orv pulverulcnt substances, particularly ores, blast furnace dust, and the like, so as to form such substances into coherent masses or bodies.

I have heretofore secured British LettersPatent No. 28,019 of December 21st, 1904, setting forth a process in which very finely ground silicious material-is mixed with lime and with the substance to be agglomerated, and thereupon exposed to the action of steam under pressure. I have discovered-that results of an exceedingly eflicient character are obtained if the silicious material and the lime are ground togetherso that the. silicious material in being broken up will also'exert a grinding action upon the lime and the small particles of silicious material which are the result of the operation will be coveredwith lime dust, and, as it were,

enveloped therein so that a very energetic re-action blast furnace slag.

will occur when the mixture is thereafter exposed tothe influence of steam.

In detail I may proceed as follows: I take a suitable silicious material such as sand, quartz or flint, and a suitable amount of lime, which term I desire to be understood in the commercial sense so as to include both material which contains only calcium compounds, and also material which in addition contains magnesium compounds;-as equivalents of lime, I may emthe same degree of fineness, that is, which will pass through sieves of the same mesh. This breaking up of the silicious material into very small particles of irregular shape as distinguished from the approximatcly globular shape which even fine sand particleshave in nature, promotes the re-action taking. place later on, by very largely increasing the surface of the particles of silicious material while at the same time reducing their thickness. By grinding thesilicious material together with the limo I not only secure a very intimate mixt'u reof the two ingredients which in itself will promote a thorough re-action, butfurthermore, the irregular pieces of silicious material produced'by the grinding operation, themselves exert a very effective grinding action. upon the lime and con vert it into a veryfinepowder which adheres to the particles of silicious material, especially as the irregular surface of the latter offers many cracks and angles in which such lime dust may lodge. Eachof the particles of silicious material therefore becomes coated with lime dust and many of them are actually enveloped in lime dust.

Having thus produced a very intimate mixture of finely ground silicious material and pulverulent lime, I mixthis with the material to be agglomerated, such as fine ores, blast furnace dust and the like, the proportion varying, but in any event, the material to be a glomerated forms the bulk of the mixture. As a rule the admixture of the silicious material-lime'compound will be about 5 of the dust or powder to be agglomer- 1 ated. If the ore dust or other material to be agglomerated does not contain a sufficient amount of moisture, water, or its equivalent, is added, and the mixture having been preliminarily formed into coherent masses, as

t-by briquetting it in'suitable presses, is brought into a closed vessel whereit is subjected to the action of steam posed to heat in a furnace without danger of premature crumbling. The efficiency of the process is tested by the completeness of the conversion of the siliciousma terial into'silicates, and I havefound that'when proceeding as above described, aremarkably small percentage of the silicious material remains unaltered. This I ex-- plain by the fact that, as above set forth, the silicious material and the lime are very intimately'mixed, and that each particle of silicious material is ofan irregular shape which not only promotes the rc-action by affording a very large surface, but causes particlesv of the limo dust to'be retained in the cracks and angles which are formed in the silicious-material during grinding, the grinding operation not only bringing the two ingredicnis together and causing lime'dust to cover and even to envelop the particles of silicious material, but ac many forcing the lime dust intothe cracks of such silicious material. 7 I might also, after grinding the silicious material-together with the lime,'first subjectthc resulting mixture to the action of'stcam'under-pressure, so as toproduce a partial conversion into silicate, audlthen after mixing the resulting mass with the ore 01' dthr substane'e to be; agglomerated, again subject the material tothe a ction of steam'und'er pressur..

v I elaim as myvinvention: v 1 The prqcess for agglomerating nonin'ni'nnted materials," which consists in grinding to'gether sii'icious material zind lime with approximately equal proportions bf C210 and SiOg to very greet fineness, so as tosplit up the silicious material into particles of irregul anshape-coated with linie in the'presence .of two subscribing witnesses:

dixst; incbrpqrziting the mixture with-the material to be 10 agglomerated and-with moisture, and exposing the mass to the actiqnrof, steam nnd'er'pressure. I v

' In testimony whereof, ,I have hereuntosigned my name r WILHELM SCHUMACHER. 

